Abstract: A precision compensation mechanism of a full-automatic bidirectional flanging machine comprises an upper die X-direction fine adjustment assembly, an upper die Y-direction fine adjustment assembly, a lower die X-direction fine adjustment assembly and a lower die Y-direction fine adjustment assembly, wherein the fine adjustment assemblies each comprise N adjusting threaded sleeves, N adjusting screws and a threaded sleeve rotation driving device; wherein the N adjusting threaded sleeves are threaded into an upper opening or a lower opening of a C-shaped flanging beam along the length direction of an upper die or a lower die; the outer wall surfaces of the N adjusting threaded sleeves are threaded into the upper opening or the lower opening of the C-shaped flanging beam to form N screw thread pairs I with the thread pitch of P1.